x86/build: Remove -m16 workaround for unsupported versions of GCC (2838307b) · Commits · 戴 / test

Revert the following two commits: ("x86, build: Build 16-bit code with -m16 where possible") ("x86, build: Change code16gcc.h from a C header to an assembly header") Since ("Documentation: update for gcc 4.9 requirement") the minimum supported version of GCC is gcc-4.9. It's now safe to remove this code. Signed-off-by:

Nick Desaulniers <ndesaulniers@google.com> Signed-off-by:

Borislav Petkov <bp@suse.de> Reviewed-by:

Nathan Chancellor <natechancellor@gmail.com> Reviewed-by:

David Woodhouse <dwmw@amazon.co.uk> Link: https://lkml.kernel.org/r/20201201011307.3676986-1-ndesaulniers@google.com

arch/x86/Makefile

+1 −8

Original line number	Diff line number	Diff line
		@@ -24,14 +24,7 @@ endif

		# How to compile the 16-bit code. Note we always compile for -march=i386;
		# that way we can complain to the user if the CPU is insufficient.
		#
		# The -m16 option is supported by GCC >= 4.9 and clang >= 3.5. For
		# older versions of GCC, include an assembly header to make sure that
		# gcc doesn't play any games behind our back.
		CODE16GCC_CFLAGS := -m32 -Wa,$(srctree)/arch/x86/boot/code16gcc.h
		M16_CFLAGS := $(call cc-option, -m16, $(CODE16GCC_CFLAGS))

		REALMODE_CFLAGS := $(M16_CFLAGS) -g -Os -DDISABLE_BRANCH_PROFILING \
		REALMODE_CFLAGS := -m16 -g -Os -DDISABLE_BRANCH_PROFILING \
		-Wall -Wstrict-prototypes -march=i386 -mregparm=3 \
		-fno-strict-aliasing -fomit-frame-pointer -fno-pic \
		-mno-mmx -mno-sse

arch/x86/boot/code16gcc.h

deleted100644 → 0

+0 −12

Original line number	Diff line number	Diff line
		/* SPDX-License-Identifier: GPL-2.0 */
		#
		# code16gcc.h
		#
		# This file is added to the assembler via -Wa when compiling 16-bit C code.
		# This is done this way instead via asm() to make sure gcc does not reorder
		# things around us.
		#
		# gcc 4.9+ has a real -m16 option so we can drop this hack long term.
		#

		.code16gcc

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